Contents of /eclass/elisp.eclass

Sync eclasses from Emacs overlay.
elisp-common.eclass: Remove last remnants of backwards compatibility code
from elisp-site-regen which was introduced at 2007-12-01. Distinguish between
"version too low" and "could not determine version" in elisp_pkg_setup.
elisp.eclass: Return 2 as exit status of elisp-need-emacs if the comparison
could not be done, e.g., if emacs could not be executed.